Telescopic sights have experienced significant development in recent decades, particularly for hunting purposes, but also for military use. They typically consist of a matted metal housing, generally cylindrical in shape, at each end of which a tube comprising ocular and/or objective optics is disposed, and between these, a reversing assembly for image erection. In this center, narrower tubular region, a reticle is also provided, i.e., the target mark preferably mounted in the lens image plane. For adjusting said reticle, a mechanical adjustment mechanism projecting radially outward from the center tubular region, for example, an adjustment screw according to DE 32 08 814 A1 or DE 37 37 856 A1 is generally used.
It is critical to enable adjustment such that the point of aim and the position of the point of impact coincide. If target distances fluctuate substantially, parallax-based deviations in the target image plane from the reticle plane can be extremely disruptive. Therefore, compensation for parallax is essential. Traditionally, this is accomplished by displacing the objective lens axially. Manufacturing tolerances and crosswinds can lead to lateral deviations, which must be corrected using a lateral adjustment device.
To adjust the reticle, therefore, at least two adjustment towers are mounted on the exterior of the telescopic sight, spaced 90 degrees around the circumference thereof, each of which comprises an adjustment device in the form of a click-stop ring or an adjusting cap. A first and a second adjustment tower are used for vertical and for lateral adjustment.
For example, DE 297 207 37 U1 describes a telescopic sight having a tubular housing, which comprises tubular mounts for eyepiece and lens positioning. In this case, an optical reversing assembly and a reticle assigned thereto are provided in a center tube, said reticle being securely mounted in a frame on the double tube. A drive mechanism equipped with threading is guided in a slot in the tubular body, and presses forward toward the reversing assembly against the force of a spring. It can be moved forward and backward in its longitudinal direction by rotating the adjustment device.
An adjustment unit of this type, which is capable of rotating a total of approximately 360 degrees, ordinarily has a fine click-stop mechanism, which is subdivided such that as the unit is rotated (click-stop adjustment) it moves a step farther with each click, thereby adjusting the position of the point of impact of 100 m by 10 mm, for example. On the outer periphery of the adjustment tower, a scale is applied, on which the correction that is made can be read during daylight hours. Depending upon the subdivision, for example, each click is marked by a white line, whereas every tenth click is identified by a number.
For sharpshooting or other special purposes, particularly with shooting ranges of up to 2,000 m, a click-stop, i.e., a single click, corresponds to an adjustment in the point of impact of up to 200 mm. It is therefore necessary for the shooter to know the precise adjustment position of the reticle device.
An adjustment tower for lateral adjustment is similar in embodiment.
However, it is problematic with the known embodiments of the prior art that the reticle device can become unintentionally displaced when the shooting location is changed. For example, displacement can occur by an article of clothing rubbing against one of the adjustment devices. Therefore, in the prior art, various devices have been developed that enable the adjustment devices to be arrested.
To perform a selective and verifiable adjustment in the dark, the shooter must detect, by touch or by sensory motor means, the number of click stops that are traceable in the adjustment to a desired adjustment position or fixing of the adjustment device, i.e., the user must sense each click-stop process and must be able to determine the precise adjustment position on the basis of the number of click stops. With a fine click-stop mechanism, and associated with this, a large adjustment range, the danger exists that the user will lose count during adjustment, and therefore, a reliable adjustment is not ensured.
Furthermore, the reticle is difficult to read in the dark. Therefore, with modern telescopic sights for hunting, the trend is toward models having so-called lighted reticles. With such embodiments, part of the reticle, for example, the target point or crosshairs, can be illuminated, in order to obtain increased contrast of the reticle, or of a part thereof, depending upon the application.
Embodiments currently on the market are controlled on the device itself, specifically using a combined on/off switch and brightness controller. A viewing device of this type is known from DE 199 13461 A 1, wherein the illumination device is embodied as an attachment for a conventional telescopic sight having a non-illuminated reticle. The illumination also allows an adjustment scale for parallax to be visualized in the optics of the telescopic sight, which scale can be easily read by the shooter, even in the dark. The brightness of the illumination can be adjusted to the existing light conditions using the illumination adjustment device.
For actuating an illumination device of this type, for example, DE 297 20 737 U1 provides a lighting adjustment device which is such that a third adjustment tower is arranged on the telescopic sight.
Also known on the market are adjustment towers from Premier Reticles and from Nightforce, which comprise an adjustment tower for telescopic sights having two adjustment devices, particularly for a combination of illumination adjustment and parallax adjustment.
Models from Nightforce are equipped with adjustment towers having a rotatable parallax adjustment device and an ON/OFF switch for adjusting illumination.
Telescopic sights from Premier Reticles have an adjustment tower consisting of a first adjustment device and a second adjustment device, which can be rotated independently of one another relative to a base, wherein the first adjustment device can be rotated into an adjustment position and has a secured position in which it is secured against rotation, and the first adjustment device can be moved axially relative to the base to a limited extent such that in the first adjustment position, said adjustment device projects further out of the second adjustment device than in the secured position.
The disadvantage of this prior art is that the shooter must pull the first adjustment device out of the second adjustment device in order to rotate it. Therefore, the shooter must be able to securely grasp the first adjustment device. For this purpose, the prior art provides a collar, which is relatively wide, so that the shooter can easily grasp it. Accordingly, the first adjustment device also projects relatively far forward in the secured position. Nevertheless, pulling the devices apart is relatively inconvenient for the shooter. Additionally, in principle, the first device for adjusting illumination is required only in the dark, and in light conditions the projection forms more of an obstacle for the shooter.
It is a further disadvantage that the first adjustment device can be moved to the secured position in only one angle of rotation, more particularly, the light-OFF position. To turn the light on again, the first adjustment device must therefore be rotated back to the desired light intensity. During the time required for this step, the target could have moved out of shooting range.
In addition, the greater structural height of the adjustment tower acts as a lever arm when handled, and can also become caught more easily on objects, such as a tree, a stone, etc. The larger the lever arm is, the greater the risk of plastic deformations such that point of aim and point of impact no longer coincide.